1. Field of the Invention
The present invention relates to hot melt compositions and processes for forming the same.
2. Description of the Prior Art
Hot melt compositions and methods for forming the same as well known in the art.
The prior art as illustrated by the identified patents deal with urethane thermoplastic elastomer, molding compounds, gasketing and other areas--none of these patents nor other literature or additional prior art denotes materials having low melt viscosity, elastomeric materials with high physical properties and melt stability.
The identified patents are:
U.S. Pat. No. 3,886,182 Olstowski. The patent describes thermosetting (rapid setting or instant set), non-elastomeric plasticized urethane molding compounds with a polyol functionality of 3-8. The main purpose of the plasticizer is to make the compound readily demoldable.
U.S. Pat. No. 3,684,639 Wolfgang Keberie. The patent deals with textile sealing adhesives dealing with specific polyglycols and an aliphatic isocyanate. Differences are that it pertains to an unplasticized composition normally polymerized in solution or applied as a powder. Although the invention deals with thermoplastics, they are not hot melt materials.
U.S. Pat. No. 3,834,578 David Smith. This patent deals with liquid casting urethanes useful for foamable gaskets, but not applied as hot melt, does not contain plasticizers and the rest of the chemistry is also not similar.
U.S. Pat. No. 3,640,937 Wilhelm Thoma. The patent deals with linear elastomer fibers composed of specific dihydrazide chain extenders. The reaction is carried out in solvents and does not cover plasticizers.
U.S. Pat. No. 269,945 James A. Vanderhider. The patent deals with a foam molding compound, not a thermoplastic hot melt compound. Liquid reactants are used in the process and the final product is a solid material.
U.S. Pat. No. 4,101,439 David Russell. This patent deals with a thermoplastic composition containing no plasticizer and does not function as a hot melt material.